Question

What does the following code print? System.out.print("*"); System.out.println("***"); System.out.println("*****"); System.out.print("****"); System.out.println("**");

Short answer

***************

Step-by-step solution

Understanding the Java Code

Analyze each line of the Java code to understand what each statement is designed to do. The 'System.out.print' command prints the string inside the quotation marks but does not move to a new line after printing. The 'System.out.println' command prints the string and moves to a new line.

Execute Line by Line

Execute each line of code in the sequence given to determine the output. The first line will print an asterisk. The second line prints three asterisks and moves to a new line. The third line prints five asterisks and moves to a new line. The fourth line prints four asterisks but does not move to a new line. The fifth line prints two asterisks and moves to a new line.

Combine the Outputs

Combine the outputs from each line to form the complete output, making sure to account for newline characters where 'println' is used and no newline characters where 'print' is used.

Key concepts

System.out.print

When learning Java, one of the first methods you'll encounter for displaying output is System.out.print. This method is used to send arguments, typically strings of text, to the console, but unlike other methods, it does not add a newline character after the output. In simple terms, if you were to use System.out.print to print multiple items, they would all appear on the same line. This is equivalent to writing with a pen without lifting it to move to the next line.

Enhancing your understanding with an exercise, imagine if the provided code was solely comprised of System.out.print statements. The result would be a continuous line of asterisks without any breaks, creating a single, long line of text.

System.out.println

Contrary to System.out.print, the System.out.println command in Java has a small but significant difference: it adds a newline character after outputting the text. This means that each call to System.out.println will finish by moving the cursor to the beginning of the next line. It's like hitting the 'Enter' key after typing something out. The result is that subsequent output will start on a new line.

Considering the exercise, each asterisk pattern printed using System.out.println appears on a separate line due to this newline character. It's this behavior that shapes the final structure of the pattern printed by the combination of print and println statements in the code.

Java Basic Syntax

Java’s basic syntax sets the rules for how the language is written and how the program will be executed. Key elements include case sensitivity, class names starting with an uppercase letter, method names starting with a lowercase letter, and every statement must end with a semicolon. Understanding how to structure statements and organize code is crucial for any programmer.

In the context of our exercise, the proper use of semicolons and method calls are textbook examples of following Java's syntax rules. If one were to miss a semicolon or mismatch case usage, the code wouldn't compile, underscoring the importance of attention to syntax details for a functional program.

Controlling Output Format

Controlling the output format in Java enables developers to present data in a clear and organized way. This is important not only for readability but also for ensuring that the output meets the requirements of the given problem or exercise.

For instance, if we revisit our exercise, the output format is controlled by wisely selecting between System.out.print and System.out.println statements to achieve the desired pattern. If more advanced formatting were needed, Java provides additional tools like printf or String.format to control things like decimal places, spacing, and text alignment. These tools are indispensable for creating visually consistent and professional-looking output.